Please find below some performance comparison we've done for a set of most popular mini cpu-boards evaluated for OGN receivers.
In our tests we used sysbench in different configurations.

Please note the results are ordered from most-performant (left) to least performant (right).

Benchmarks

ODROID-XU4 (Exynos5422 Cortex-A15 2Ghz and Cortex-A7 8-cores)

ODROID-U3 (Exynos4412 Prime Cortex-A9 4-cores)

Raspberry Pi3 (1.2GHz 64-bit 4-core ARM Cortex-A53 (~10x Pi1 perf))

Rockchip RK3188 (e.g. MK809 IV 4-cores)

Odroid-C1 (ARM Cortex-A5 4-cores)

OrangePi One (Allwinner H3 Cortex A7 4-cores)

Raspberry Pi2 (900MHz 4-core ARM Cortex-A7 CPU (~6x Pi1 perf))

Olimex A20-OLinuXino-LIME (ARM Cortex-A7 2-cores)

Banana Pi (ARM Cortex-A7 2-cores)

Cubieboard3 (ARM Cortex-A7 2-cores)

Cubieboard2 (ARM Cortex-A7, 2-cores)

BeagleBone Black (ARM Cortex-A7, 1-core)

Raspberry Pi Zero W(ARM1176JZF-S (ARMv6k) 1-core)

BeagleBone (ARM Cortex-A8, 1-core)

Raspberry Pi (ARM1176JZF-S (ARMv6k) 1-core)

Price

74$ (http://hardkernel.com + 19$ for shipping!) 80€ (http://pollin.de)

65$ (http://hardkernel.com + 25$ for shipping!) 70€ (http://pollin.de)

~43$ 39€ (http://pollin.de)

~44-50$ (ebay) 45€ (http://amazon.de)

44€ (http://pollin.de)

$9.99 + ~$4 shipping (aliexpress)

~40$ 37€ (http://pollin.de)

33€ (https://www.olimex.com) 40€ (http://exp-tech.de)

~40€, 75€ (kit) (amazon) 35€ (http://redcoon.de)

88€ (http://pollin.de)

~68$ 63€ (http://pollin.de) _ 58€(ebay, free shipment)

48€ (http://pollin.de)

11€ (https://www.kiwi-electronics.nl)

78€ (http://rs-components.com)

~48$ 30€ (http://pollin.de)

CPU

1 Thread

8.7536s

13.9420s

19.6445s

15.1796s

23.8167s

24.8021s

31.0962s

28.6889s

29.5346s

29.0845s

32.6901s

29.4214s

37.3745s

40.9213s

54.0791s

2 Threads

4.3783s

6.9756s

9.8471s

8.4593s

11.5903s

12.4252s

15.6131s

14.4584s

14.4951s

14.6567s

20.4404s

29.3900s

37.4377s

40.7818s

54.2914s

4 Threads

2.1944s

3.4863s

4.9428s

5.0010s

5.8368s

6.2781s

7.8286s

14.4678s

14.5026s

14.7216s

20.3010s

29.3866s

37.4271s

40.8213s

54.2213s

MEMORY

256M

5109.55 MB/sec

3567.99 MB/sec

1531.52 MB/sec

1908.11 MB/sec

1448.41 MB/sec

1075.59 MB/sec

1045.95 MB/sec

1253.92 MB/sec

1147.46 MB/sec

1131.00 MB/sec

1027.03 MB/sec

560.11 MB/sec

405.59 MB/sec

564.73 MB/sec

352.03 MB/sec

512M

5132.19 MB/sec

4192.24 MB/sec

1928.87 MB/sec

2022.42 MB/sec

1445.04 MB/sec

1363.81 MB/sec

2140.72 MB/sec

1255.08 MB/sec

1175.29 MB/sec

1084.75 MB/sec

1044.92 MB/sec

883.35 MB/sec

406.97 MB/sec

760.91 MB/sec

352.66 MB/sec

Notes

Following commands were used to test the board:

1 Thread:  sysbench --num-threads=1 --test=cpu --cpu-max-prime=2000 run
2 Threads: sysbench --num-threads=2 --test=cpu --cpu-max-prime=2000 run
4 Threads: sysbench --num-threads=4 --test=cpu --cpu-max-prime=2000 run
256M: sysbench --test=memory --memory-block-size=1M --memory-total-size=256M run
512M: sysbench --test=memory --memory-block-size=1M --memory-total-size=512M run

Conclusions

For new installations it is strongly recommend investing in multi-core (at least 2 cores) hardware, as single-core mini boards may have problems dealing with intensive traffic. If in addition to OGN receiver software you plan to run other software on the same hardware (e.g. you are active feeder of ADS-B data to FR24), then definitely do not consider any single-core solution.

If, however, you already have one or you can get one really cheap - for now we recommend to go for Raspberry Pi! because of these reasons:

1. OGN receiver software is able to use GPU on Raspberry Pi (and that significantly improves performance, although e.g. BeagleBone Black without the use of GPU proves to offer similar performance as Pi with GPU)
2. The Raspberry community is by far the biggest community. If you have a question or a special problem, then the probability is very high you get a solution if you use a Raspberry Pi